Cambodia records the country's first known human case of H5N1 bird flu in nine years. We have been monitoring the virus and outbreaks in birds, mammals as well as sporadic human cases around the world. Human cases of bird flu may be rare but cases of bird flu have increased globally.  International SOS Medical Director, Dr Kate O'Reilly and Global Medical Director Dr Irene Lai discuss the severity of the situation and whether it could become the next pandemic.